Let \[f(x) =
\begin{cases}
2x + 9 &\text{if }x<-2, \\
5-2x&\text{if }x\ge -2.
\end{cases}
\]Find $f(3).$
Explanation: Because $3\ge -2,$ we use the second case to determine that $f(3) = 5-2(3) = \boxed{-1}.$